Prince William, Kate and Prince Harry showed their competitive sides as they took part in a relay race against each other for their mental health campaign, Heads Together.

The trio were joined by around 150 runners who were training for the London Marathon at the Queen Elizabeth Olympic Park on Sunday.

Although Prince William pretended to have pulled a muscle prior to the race, jokily saying: "Oh my hamstring!" it seemed that all three were determined to win and readied themselves for the 50-metre sprint.

They also took time to reinforce the campaign's core message, "When we get our #headstogether we can achieve great things! Together we can end the stigma once and for all #mentalhealth."

Click through for all of the best pictures from the event and to find out who won the race!

The competitive couple tried to psych each other out prior to the race.